Development of an Active Biomimetic-Controlled Transfemoral Knee Prosthesis

2016 ◽  
Author(s):  
Mario G. Bernal-Torres ◽  
Hugo I. Medellín-Castillo ◽  
Juan C. Arellano-González
Keyword(s):  
Gait Cycle ◽  
Knee Prosthesis ◽  
Control Strategies ◽  
Human Motion ◽  
The Body ◽  
Metabolic Energy ◽  
Knee Prostheses ◽  
Additional Energy ◽  
Long Time ◽  
Four Bar Linkage

Commercial available knee prostheses are still limited because most of them comprise passive elements that store and deliver energy during the gait cycle, but without providing additional energy. This inability to provide additional energy affects the performance of passive prostheses, which in some cases demands up to 60% of additional metabolic energy to perform a gait cycle. Recent research works have focused on the design of active knee prostheses, including the development and implementation of control strategies such as electromyographic (EMG) signals. However, the results of such implementations reveal that these control strategies are still limited because of the relatively long time response and inaccurate movements. This paper presents the design of a new biomimetic-controlled knee prosthesis for transfemoral amputation. The aim is to contribute to the development of simple and effective active knee prostheses. The proposed prosthesis consists of a polycentric mechanism obtained from the body-guidance kinematics synthesis of a four bar linkage. This synthesis is based on the natural movements of the human knee, taking into account the shortening effect of the leg during the walking process to avoid trips. The prosthetic knee mimics the human motion of the healthy leg by means of an echo-control strategy. An experimental prototype has been implemented and tested on a workbench. The experimental results have demonstrated the usability of the proposed biomimetic active knee prosthesis.

scholarly journals Design and Control of a New Biomimetic Transfemoral Knee Prosthesis Using an Echo-Control Scheme

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Mario G. Bernal-Torres ◽  
Hugo I. Medellín-Castillo ◽  
Juan C. Arellano-González
Keyword(s):  
Control Strategy ◽  
Knee Prosthesis ◽  
The Body ◽  
Metabolic Energy ◽  
Knee Prostheses ◽  
Human Knee ◽  
Knee Movement ◽  
Control Scheme ◽  
Sound Side ◽  
And Control

Passive knee prostheses require a significant amount of additional metabolic energy to carry out a gait cycle, therefore affecting the natural human walk performance. Current active knee prostheses are still limited because they do not reply with accuracy of the natural human knee movement, and the time response is relatively large. This paper presents the design and control of a new biomimetic-controlled transfemoral knee prosthesis based on a polycentric-type mechanism. The aim was to develop a knee prosthesis able to provide additional power and to mimic with accuracy of the natural human knee movement using a stable control strategy. The design of the knee mechanism was obtained from the body-guidance kinematics synthesis based on real human walking patterns obtained from computer vision and 3D reconstruction. A biomechanical evaluation of the synthesized prosthesis was then carried out. For the activation and control of the prosthesis, an echo-control strategy was proposed and developed. In this echo-control strategy, the sound side leg is sensed and synchronized with the activation of the knee prosthesis. An experimental prototype was built and evaluated in a test rig. The results revealed that the prosthetic knee is able to mimic the biomechanics of the human knee.

scholarly journals Review of Recent Progress in Robotic Knee Prosthesis Related Techniques: Structure, Actuation and Control

2021 ◽  
Vol 18 (4) ◽  
pp. 764-785
Author(s):  
Yuanxi Sun ◽  
Hao Tang ◽  
Yuntao Tang ◽  
Jia Zheng ◽  
Dianbiao Dong ◽  
...  
Keyword(s):  
Recent Progress ◽  
Mechanical Performance ◽  
Control Method ◽  
Mechanical Design ◽  
Knee Prosthesis ◽  
Control Strategies ◽  
Knee Prostheses ◽  
Mode Identification ◽  
Gait Adaptation ◽  
Saving Effect

AbstractAs the essential technology of human-robotics interactive wearable devices, the robotic knee prosthesis can provide above-knee amputations with functional knee compensations to realize their physical and psychological social regression. With the development of mechanical and mechatronic science and technology, the fully active knee prosthesis that can provide subjects with actuating torques has demonstrated a better wearing performance in slope walking and stair ascent when compared with the passive and the semi-active ones. Additionally, with intelligent human-robotics control strategies and algorithms, the wearing effect of the knee prosthesis has been greatly enhanced in terms of stance stability and swing mobility. Therefore, to help readers to obtain an overview of recent progress in robotic knee prosthesis, this paper systematically categorized knee prostheses according to their integrated functions and introduced related research in the past ten years (2010–2020) regarding (1) mechanical design, including uniaxial, four-bar, and multi-bar knee structures, (2) actuating technology, including rigid and elastic actuation, and (3) control method, including mode identification, motion prediction, and automatic control. Quantitative and qualitative analysis and comparison of robotic knee prosthesis-related techniques are conducted. The development trends are concluded as follows: (1) bionic and lightweight structures with better mechanical performance, (2) bionic elastic actuation with energy-saving effect, (3) artificial intelligence-based bionic prosthetic control. Besides, challenges and innovative insights of customized lightweight bionic knee joint structure, highly efficient compact bionic actuation, and personalized daily multi-mode gait adaptation are also discussed in-depth to facilitate the future development of the robotic knee prosthesis.

scholarly journals Analisis Kinematis untuk Menentukan Dimensi Transfemoral Prosthetic Tipe Four-Bar Linkage dalam Fase Awal Siklus Gait Cycle

ROTASI ◽  
2017 ◽  
Vol 19 (2) ◽  
pp. 61
Author(s):  
Sugiyanto Sugiyanto ◽  
Biyan B. P. ◽  
Alhakim B. P. ◽  
Dwi Setyawan ◽  
Rifky Ismail
Keyword(s):  
Gait Cycle ◽  
Knee Prosthesis ◽  
Four Bar Linkage

Produk kaki tiruan atas lutut atau sering disebut sebagai above knee prosthesis (AKP) yang memiliki sendi lutut tiruan berbasis kinerja mekanis masih didominasi oleh produk impor. Produk AKP domestik masih berkonsentrasi pada sistem sendi konvensional. Untuk pasar AKP dengan segmen menengah ke atas yang menghendaki fleksibilitas gerak, kenyamanan, fungsi kaki yang optimal dan kemudahan pengaturan, masyarakat Indonesia masih tergantung terhadap produk impor. Penelitian ini bertujuan untuk melakukan analisis kinematika pada suatu prototipe AKP yang difokuskan pada bagian transfemoral prosthetic dengan sendi mekanis untuk substitusi produk impor. Bagian transfemoral prosthetic pada prototipe AKP yang dibahas adalah jenis four-bar linkage. Analisis yang digunakan adalah hubungan antara dimensi four-bar linkage  selama satu siklus gait cycle orang berjalan normal. Siklus gait cycle ini berpengaruh terhadap besarnya sudut yang terbentuk antara sumbu knee ankle (KA) dengan sumbu trocenter knee (TK). Sesuai dengan fungsi AKP, maka penting untuk mendapatkan data teknis tentang hubungan dimensi four-bar linkage pada transfemoral prosthetic. Hasil analisis gerak selama satu siklus gait cycle orang berjalan normal menunjukkan dimensi four bar linkage adalah a = 10 mm, b = 34 mm, c = 15 mm, d = 30 mm, e = 28 mm dan f = 46 mm.

LUBRICATION PREDICTIONS FOR TOTAL KNEE PROSTHESIS MADE OF HARD MATERIALS

2015 ◽  
Vol 45 (1) ◽  
pp. 45-50
Author(s):  
J. DI PAOLO ◽  
M. E. BERLI
Keyword(s):  
Gait Cycle ◽  
Knee Prosthesis ◽  
Knee Prostheses ◽  
Total Knee Prosthesis ◽  
Hard Materials ◽  
Lubrication Regime ◽  
Total Knee ◽  
Lubricated Contact ◽  
Film Lubrication ◽  
Generalized Reynolds Equation

The lubricated contact zone in a total knee prosthesis is modeled, where femoral and tibial components are supposed to be made of hard materials (high stiffness and hardness) and lubricated by a non Newtonian fluid (synovial liquid). To determine optimal relations among geometric parameters, load and film thickness, a generalized Reynolds equation was solved by means of finite element method. Although mix lubrication regime is predominant, it is shown that increasing conformity, it could be assure a full-film lubrication regime in most of the gait cycle. These results might be a reference to make more durable total knee prostheses.

scholarly journals Sit-to-Stand Control of Powered Knee Prostheses

2017 ◽  
Author(s):  
Molei Wu ◽  
Md Rejwanul Haque ◽  
Xiangrong Shen
Keyword(s):  
Knee Prosthesis ◽  
Single Equation ◽  
The Body ◽  
Knee Prostheses ◽  
Major Barrier ◽  
Control Approach ◽  
Biomechanical Behavior ◽  
Sit To Stand ◽  
Reaction Forces ◽  
Prosthesis Control

Standing from a seated position is a common, yet dynamically challenging task. Due to the vertical ascent of the body center of gravity, sit-to-stand (STS) transition requires high torque output from the knee. As a result, STS transition poses a major barrier to the mobility of individuals with lower-limb issues, including the transfemoral (TF, also known as above-knee) amputees. A study showed that unilateral TF amputees suffer from high asymmetry in ground reaction forces (53∼69%) and knee moments (110∼124%), while the asymmetry for healthy controls is less than 7% [1]. Note that, although a powered TF prosthesis (Power Knee™) was used in this study, it generated resistance in the STS and thus produced similar results as the passive devices. The inability of existing prostheses in generating knee torque and regulating the torque delivery in the STS seriously affects the mobility of TF amputees in their daily life. Motivated by this issue, researchers have developed numerous powered TF prostheses (e.g., Vanderbilt powered TF prostheses [2]). These devices are able to generate torque and power for challenging tasks such as STS transition. Making full use of such capability, however, requires an effective controller. Currently, walking control for powered prostheses has been well established, but STS control is much less investigated. Varol et al. developed a multi-mode TF prosthesis controller, in which STS is treated as a transitional motion between sitting and standing states [2]. However, no details were provided on the rationale of the STS controller structure or the determination of the control parameters. In this paper, a new prosthesis control approach is presented, which regulates the power and torque delivery in the STS process. Inspired by the biomechanical behavior of the knee in the STS motion, the new controller provides two desired functions (gradual loading of the knee at the beginning, and automatic adjustment of the knee torque according to motion progress) with a single equation. Combined with a simple yet reliable triggering condition, the proposed control approach is able to provide natural STS motion for the powered knee prosthesis users.

Dynamic Optimization of Human Walking

2001 ◽  
Vol 123 (5) ◽  
pp. 381-390 ◽  
Author(s):  
Frank C. Anderson ◽  
Marcus G. Pandy
Keyword(s):  
Dynamic Optimization ◽  
Gait Cycle ◽  
Three Dimensional ◽  
Optimization Theory ◽  
The Body ◽  
Metabolic Energy ◽  
Unit Distance ◽  
Terminal Constraints ◽  
Muscle Activations ◽  
The Right

A three-dimensional, neuromusculoskeletal model of the body was combined with dynamic optimization theory to simulate normal walking on level ground. The body was modeled as a 23 degree-of-freedom mechanical linkage, actuated by 54 muscles. The dynamic optimization problem was to calculate the muscle excitation histories, muscle forces, and limb motions subject to minimum metabolic energy expenditure per unit distance traveled. Muscle metabolic energy was calculated by summing five terms: the basal or resting heat, activation heat, maintenance heat, shortening heat, and the mechanical work done by all the muscles in the model. The gait cycle was assumed to be symmetric; that is, the muscle excitations for the right and left legs and the initial and terminal states in the model were assumed to be equal. Importantly, a tracking problem was not solved. Rather, only a set of terminal constraints was placed on the states of the model to enforce repeatability of the gait cycle. Quantitative comparisons of the model predictions with patterns of body-segmental displacements, ground-reaction forces, and muscle activations obtained from experiment show that the simulation reproduces the salient features of normal gait. The simulation results suggest that minimum metabolic energy per unit distance traveled is a valid measure of walking performance.

The use of acidifying agents Aquasafe and Veleguard when rearing of broiler chickens

2020 ◽  
pp. 16-27
Author(s):  
L. Gamko ◽  
T. Tarinskaya
Keyword(s):  
Drinking Water ◽  
Organic Acids ◽  
Broiler Chickens ◽  
Positive Impact ◽  
The Body ◽  
Metabolic Energy ◽  
Control Group ◽  
Meat Production ◽  
Feed Conversion ◽  
Broiler Meat

It is known that necessary to replace the components of organic acids, which are part of acidifiers when drinking water to poultry in order to prevent the adaptation of microbes in the gastrointestinal tract. In the poultry industry organic acids are widely used, which are used as acidifiers to preserve the properties of water consumed. The purpose of this work was to evaluate the efficiency of broiler meat production when using acidifying agents of drinking water Aquasafe and Veleguard. The experimental part of the work has been performed in JSC “Kurinoe Tsarstvo-Bryansk” broiler area “Roshcha” in the Pochepsky district. The object of research was the livestock of broiler chickens cross Cobb 500 at floor housing. The effect of water acidifiers on meat productivity has been studied. Groups of chickens have been formed on the principle of pairs-analogues. Broiler chickens of experimental groups have been separated from the main livestock by a grid in the corner of the room for 100 heads in each group. It has been found by a result of research to be optimal dose usage of acidifying agents water Aquasafe and Veleguard to drink to broiler chickens. The positive effect of these acidifiers on the digestion of crude protein, crude fat, crude fiber, contributing to the effective use of nitrogen, which led to an increase in the intensity of growth, young animals’ livability and improved feed conversion. Slaughter yield in the control group was 55,1 %, and in the experimental group 57,2 and 58,4 %, which was by 2,1 and 3,3 % higher with the same level of metabolic energy and nutrients. In chickens that consumed acidifi ers more intensively used nutrients feed for deposition in the body of the components of the carcass, which affected the production. A positive impact of acidifying agents Aquasafe and Veleguard on meat quality in broiler chickens has been found.

Indicators of metabolism and biochemical status of blood in horses of Yakut breed in winter and spring seasons

2020 ◽  
pp. 52-65
Author(s):  
U. Khompodoeva ◽  
R. Ivanov
Keyword(s):  
Classical Method ◽  
Live Weight ◽  
Weather Conditions ◽  
The Body ◽  
Metabolic Energy ◽  
Temperature Changes ◽  
Experimental Animals ◽  
Spring Period ◽  
Biochemical Status ◽  
Adaptive Mechanisms

The results of researches on the peculiarities of metabolism in the body of horses of Yakut breed in the winter and spring periods under the environments of Central Yakutia have been presented in the article. Physiological experiments on the digestibility of the main nutrients of the feed have been carried out in the winter (February) and spring (April) periods under the environments of the physiological yard in the Yakutsk Scientific and Research Institute of Agriculture named after M. G. Safronov with using the classical method. Five mares and five geldings of Yakut breed have been selected for researches. The average live weight of mares was 378–410 kg, geldings 394–403 kg. The experimental animals had average fatness. It has been found a higher intake of energy and the main nutrients of hay as a mono feed in winter compared to the spring period. At the same time pregnant mares in winter have been consumed 103,8±3,12 MJ of metabolic energy per head/day, which was 27,3 % significantly higher than in the spring period – 75,4±2,18 MJ (P ≥ 0,999). Geldings have been consumed in the experiment 67,70±2,85 MJ, which was by 43,7 % higher than in the spring period – 38,05 ± 4,40 MJ of metabolic energy per head/day (P ≥ 0,999). Experimental animals have been housed in stalls; there was no energy expenditure for movement, so the amount of energy consumed in winter indicates the production of heat in the animal’s body. Pregnant mares per 100 kg of live weight have consumed 31,5±4,11 MJ of metabolic energy or 33,3 % more than in the spring period – 21,0±1,98 MJ; geldings have consumed 27,69±1,12, which was 41,78 % significantly higher than in the spring – 16,12 ± 0,75 MJ (P ≥ 0,999). The high intake of metabolic energy into the body of Yakut horses in winter is explained by the manifestation of adaptive mechanisms that affect the effective metabolism for survival, adapted to frequent changes in weather conditions and sharp temperature changes. The established differences in the biochemical parameters of blood serum of horses of Yakut breed are associated with changes in the consumption and digestibility of basic nutrients and energy, depending on the ambient temperature.

scholarly journals Analysis of Friction in Total Knee Prosthesis during a Standard Gait Cycle

Lubricants ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 36
Author(s):  
Matúš Ranuša ◽  
Markus A. Wimmer ◽  
Spencer Fullam ◽  
Martin Vrbka ◽  
Ivan Křupka
Keyword(s):  
Total Knee Replacement ◽  
Knee Replacement ◽  
Computational Models ◽  
Gait Cycle ◽  
Knee Prosthesis ◽  
Shear Stresses ◽  
Cobalt Chromium ◽  
Joint Friction ◽  
The Coefficient Of Friction ◽  
Total Knee

Total knee arthroplasty is on the rise worldwide. Despite its success, revision surgeries are also increasing. According to the American Joint Replacement Registry 2020, 3.3% of revision surgeries are due to wear, and 24.2% are due to mechanical loosening. The combination of shear stresses and wear particles occurring at the bone/implant interface can lead to local osteolysis. Although the shear stresses are partially driven by joint friction, relatively little is known about the evolution of the coefficient of friction (CoF) during a gait cycle in total knee replacement. Here we describe the CoF during a gait cycle and investigate its association with kinematics (slide–roll-ratio), applied load, and relative velocity. The artificial knee was simulated by cobalt–chromium condyle on a flat ultra-high-molecular-weight polyethylene (UHMWPE) tibial plateau, lubricated by either water or proteinaceous solution. We found that the CoF is not a constant but fluctuates between the values close to 0 and 0.15. Cross-correlation suggested that this is primarily an effect of the slide–roll ratio and the contact pressure. There was no difference in the CoF between water and proteinaceous solution. Knowledge about the CoF behavior during a gait cycle will help to increase the accuracy of future computational models of total knee replacement.

scholarly journals Development of Novel Oral Formulations of Disulfide Antioxidants Based on Porous Silica for Controlled Release of the Drugs

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 963
Author(s):  
Ekaterina S. Dolinina ◽  
Elena V. Parfenyuk
Keyword(s):  
Antioxidant Activity ◽  
Surface Chemistry ◽  
Sol Gel ◽  
Porous Silica ◽  
The Body ◽  
Oral Drug ◽  
Therapeutic Concentration ◽  
Release Process ◽  
Zero Order Kinetics ◽  
Long Time

Powerful antioxidant α-lipoic acid (LA) exhibits limited therapeutic efficiency due to its pharmacokinetic properties. Therefore, the purpose of this work was to evaluate the ability of silica-based composites of LA as well as its amide (lipoamide, LM), as new oral drug formulations, to control their release and maintain their therapeutic concentration and antioxidant activity in the body over a long time. The composites synthesized at different sol–gel synthesis pH and based on silica matrixes with various surface chemistry were investigated. The release behavior of the composites in media mimicking pH of digestive fluids (pH 1.6, 6.8, and 7.4) was revealed. The effects of chemical structure of the antioxidants, synthesis pH, surface chemistry of the silica matrixes in the composites as well as the pH of release medium on kinetic parameters of the drug release and mechanisms of the process were discussed. The comparative analysis of the obtained data allowed the determination of the most promising composites. Using these composites, modeling of the release process of the antioxidants in accordance with transit conditions of the drugs in stomach, proximal, and distal parts of small intestine and colon was carried out. The composites exhibited the release close to the zero order kinetics and maintained the therapeutic concentration of the drugs and antioxidant effect in all parts of the intestine for up to 24 h. The obtained results showed that encapsulation of LA and LM in the silica matrixes is a promising way to improve their bioavailability and antioxidant activity.

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